﻿/*
Usage Sample:
<script language="JavaScript">
TargetDate = "12/31/2020 5:00 AM";
BackColor = "palegreen";
ForeColor = "navy";
CountActive = true;
CountStepper = -1;
LeadingZero = true;
DisplayFormat = "%%D%% Days, %%H%% Hours, %%M%% Minutes, %%S%% Seconds.";
FinishMessage = "It is finally here!";
</script>
*/

function calcage(secs, num1, num2) {
    s = ((Math.floor(secs / num1)) % num2).toString();
    if (LeadingZero && s.length < 2)
        s = "0" + s;
    return "<b>" + s + "</b>";
}

function CountBack(secs) {
    if (secs < 0) {
        document.getElementById("cntdwn").innerHTML = FinishMessage;
        return;
    }
    DisplayStr = DisplayFormat.replace(/%%D%%/g, calcage(secs, 86400, 100000));
    DisplayStr = DisplayStr.replace(/%%H%%/g, calcage(secs, 3600, 24));
    DisplayStr = DisplayStr.replace(/%%M%%/g, calcage(secs, 60, 60));
    DisplayStr = DisplayStr.replace(/%%S%%/g, calcage(secs, 1, 60));

    document.getElementById("cntdwn").innerHTML = DisplayStr;
    if (CountActive)
        setTimeout("CountBack(" + (secs + CountStepper) + ")", SetTimeOutPeriod);
}

function putspan(backcolor, forecolor) {
    document.write("<span id='cntdwn' style='background-color:" + backcolor +
                "; color:" + forecolor + "'></span>");
}

if (typeof (BackColor) == "undefined")
    BackColor = "white";
if (typeof (ForeColor) == "undefined")
    ForeColor = "black";
if (typeof (TargetDate) == "undefined")
    TargetDate = "12/31/2020 5:00 AM";
if (typeof (DisplayFormat) == "undefined")
    DisplayFormat = "%%D%% Days, %%H%% Hours, %%M%% Minutes, %%S%% Seconds.";
if (typeof (CountActive) == "undefined")
    CountActive = true;
if (typeof (FinishMessage) == "undefined")
    FinishMessage = "";
if (typeof (CountStepper) != "number")
    CountStepper = -1;
if (typeof (LeadingZero) == "undefined")
    LeadingZero = true;


CountStepper = Math.ceil(CountStepper);
if (CountStepper == 0)
    CountActive = false;
var SetTimeOutPeriod = (Math.abs(CountStepper) - 1) * 1000 + 990;
putspan(BackColor, ForeColor);
var dthen = new Date(TargetDate);
var dnow = new Date();
if (CountStepper > 0)
    ddiff = new Date(dnow - dthen);
else
    ddiff = new Date(dthen - dnow);
gsecs = Math.floor(ddiff.valueOf() / 1000);
CountBack(gsecs);